Population density, spatial patterns and sample size of Edessa meditabunda (F., 1794) (Hemiptera: Pentatomidae) on alternative plants during soybean off-season in southern Brazil

Abstract

Edessa meditabunda (F., 1794) (Hemiptera: Pentatomidae) is considered a potential pest for soybean crops in the Neotropical region. During winter (i.e. the soybean off-season), the stink bugs seek alternative host plants such as Saccharum angustifolium (Nees) Trin. and Andropogon bicornis L. at the edge of crop fields for shelter. The objective of this study was to investigate the population density between plants and tussock diameter, spatial distribution and sample size of E. meditabunda on A. bocornis and S. angustifolium at the edge of cultivated areas during soybean off-season. In both plants, the increase of tussock diameter resulted in a higher population density of E. meditabunda. Tussocks of S. angustifolium had a higher average number of stink bugs.plant-1 than A. bicornis. We observed an aggregation trend in both plant species. For practical applicability following Integrated Pest Management, a minimum sample size of 106 and 116 plants for A. bicornis and S. angustifolium respectively was obtained. Evaluation of host plants at the edges of crop fields during soybean off-season plays an important role in management strategies during the next cropping season.